You leave the same way you would leave anyone, then you build a buffer for the eight hours a day you cannot avoid each other. Decide first, because sharing an employer is a reason to plan the exit carefully, not a reason to stay in a relationship you have already ended in your head. Then run three moving parts on purpose: the conversation off company property, the logistics that keep the split out of the org chart, and a safety layer for the version of this where he does not take no well.
The shared office makes this feel like a trap. It is not one. It is a scheduling problem wearing the costume of an impossible choice.
Most advice you will find on this treats it as an etiquette exercise. Act normal. Be professional. Avoid the coffee machine. All of that is downstream. None of it answers the only question that matters yet, which is whether you are staying because you want to or because leaving looks logistically expensive.
Decide first. The shared office is not a reason to stay
You are allowed to leave a relationship for any reason or no stated reason. Working together does not lower that bar. It just adds a to-do list after the decision.
The trap I watch people fall into is running the logistics before the verdict. You start rehearsing how you would survive the standups, whether people would talk, what the seating chart looks like in three months, and somewhere in that spiral you decide it is easier to stay. That is not a decision to stay. That is a decision to avoid a hard week.
So separate the two. First: do I want out. Then, and only then: how do I run the exit.
If you are still genuinely unsure, that is a different guide. Use the Off-Ramp criteria to decide, or read how to leave an undefined relationship without a final answer if the thing you share is more situationship than relationship. This page assumes the verdict is in. You are leaving. Now we make it clean.
The Workplace Exit Plan
The Workplace Exit Plan is three moving parts you run on purpose instead of improvising in the moment.
Part one is the conversation. Where it happens, when it happens, how long it lasts, and the rule that you do not reopen it.
Part two is the overlap buffer. The small, boring changes to your day that reduce unplanned contact so your nervous system is not braced for a run-in every time you refill your water.
Part three is the safety layer. This one is conditional. If he is kind and reasonable, it stays small and mostly unused. If he is controlling, if he has threatened you, if he uses work as leverage, this layer moves to the front and everything else waits behind it.
Run them in that order for an ordinary breakup. Reverse them the moment safety is in question. The whole point of a plan is that you decided the sequence when you were calm, not at 8:55 in the elevator when your hands are shaking.
Have the conversation off the clock and off the property
Do not break up at work. Not in a meeting room, not in the parking garage, not over the internal chat that lives on a company server your manager could theoretically read.
Pick neutral ground away from the building. A public place is better than his apartment or yours, because a public place has a natural end and a soft exit for both of you. Keep it short. State the decision as a decision, not a debate.
I have thought about this and I am ending things. I want to keep it respectful at work, so I am going to keep our conversations professional from here. I am not looking to get into all the reasons right now.
That is the whole script. You will feel the pull to soften it, to explain, to give him the five reasons so he understands. Resist that. Reasons are an opening. He answers each one, you respond, and forty minutes later you are relitigating the relationship in a coffee shop instead of leaving it.
The single-sentence version you hold in your head: I am not here to convince him, I am here to inform him.
If any part of you is scared of how he reacts, change the setup, not the decision. love is respect is blunt about this. If you break up in person, do it in a public place and have a trusted friend or family member wait nearby, and do not break up in person at all if it is not safe for you to do so. Your safety matters more than his sense of closure. Trust yourself. If you feel afraid, take the fear seriously.
Keep the split out of the org chart
Here is the part nobody tells you. The office does not need a story. It needs nothing at all.
You do not owe your team an announcement. You do not confirm to the curious. When someone fishes, the answer is a flat, friendly non-answer and a subject change. We are keeping things professional. Anyway, did the deck get sent.
The gossip dies faster than you think when neither of you feeds it. What keeps an office breakup alive is one person narrating it. Do not be that person, and do not react when he is.
Then change the small routines. This is the overlap buffer, and it is almost embarrassingly practical. Move your coffee run by twenty minutes. Take the far stairwell. Eat lunch at a different hour or off-site for a couple of weeks. If you sit near each other and it is genuinely unworkable, a quiet desk move is a reasonable ask.
Move what you can to async. Recurring one-to-ones become messages. Shared meetings become video where the format allows it. You are not disappearing. You are removing the unplanned collisions that spike your stress for no operational reason. A planned professional interaction is fine. It is the ambush at the microwave that ruins your Tuesday.
Keep your work impeccable during this stretch. Not to impress him. To make sure the only thing anyone can say about you is that your work never slipped. That protects you if the split ever gets messy, and it is the cheapest insurance you will buy all quarter.
When it is a safety problem, not an etiquette problem
Everything above assumes an ordinary ending between two adults who can behave. Some of you are not in that situation, and you know exactly who you are as you read this.
If he has controlled you, threatened you, monitored you, or used his position or the job itself as leverage, this is not an etiquette problem. It is a safety problem, and the plan changes.
The most dangerous moment in a controlling relationship is often the moment you leave. That is not a reason to stay. It is a reason to leave with a plan built for it. The Hotline lays out concrete steps for after you leave. Where possible, change your work hours and the route you take to get there, and alert colleagues about how and when to seek help if they think you may be in danger. Read that as permission to be logistical about your own safety instead of polite.
Document the behavior. Keep a factual record of anything that crosses a line, dated, saved somewhere he cannot reach. Tell one person you trust at work who is not part of the gossip layer. If he has done something HR should know, that is not you being dramatic. That is you creating a paper trail before you need one.
And do not build this alone. A trained advocate will help you think through the version of the exit that keeps both your safety and your paycheck intact, which are not opposite goals no matter how it feels at 2am. If what you are actually reading is whether his behavior is just difficult or genuinely a problem, the difference between busy and disrespectful is the clearer place to start.
What to say to HR
You go to HR when the relationship touches the work, and you skip HR when it does not.
If one of you reports to the other, or you sit on the same small team, or his conduct after the split becomes a problem, HR is a tool, not a confession booth. Keep it factual and forward-looking. Say what you need changed. Do not hand them a relationship autopsy.
I want to give you a heads up that a personal relationship has ended and I want to make sure it does not affect the team. I would like us to not be staffed on the same project going forward. My work will not change. I am just flagging it early so we can handle it cleanly.
Notice what that does. It leads with the business impact, requests a specific fix, and reassures them your output is steady. If there has been harassment or threats, that is a separate and firmer conversation, and you bring your documentation to it. But for an ordinary split that happens to sit awkwardly on the org chart, the calm early flag is almost always enough.
How to read the first two weeks
The first two weeks tell you which kind of ex you are dealing with, and you mostly just watch.
He keeps it professional and gives you room. Good. That is the outcome the whole plan is built to make easy. Hold your side, keep your routines, and let it settle.
He tries to reopen it through work. A suddenly urgent message that is not urgent. A meeting that could have been an email. Loitering near your desk. Name it once, quietly and only about work. Let's keep our messages to what the project needs. Then stop responding to the bait.
He gets cold, petty, or starts steering the office narrative. Do not match it. Keep your work clean and your record cleaner. Petty reads as petty to everyone watching, and the person who stays professional is the person who looks good in six months.
He escalates, pressures, or makes you feel unsafe. That is no longer a breakup you are managing. That is a safety situation, and you move it to the front of the plan, document it, and involve the people whose job is to handle exactly this. If you find yourself waiting for him to become reasonable so the discomfort stops, read how to stop waiting for a busy ex, because the waiting is its own trap.
My team has thousands of conversations weekly with men on the other side of exactly these splits, and the pattern barely varies. The ones who stay professional were going to stay professional. The ones who make it hard were always going to make it hard. You cannot control which one he is. You can control that your exit was clean, your work was steady, and your safety came first.
You do not have to solve working together. You have to leave, then run the plan for the overlap. The office was never the reason to stay.